How Many Chickens Do You Need to Feed 30 People Eggs

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Chapter 4: General Management

HOUSING AND RUNS

Under undomesticated conditions, poultry lay eggs in simple nests, perch in trees and spend much of the day scavenging for feed. Chickens spend a large proportion of their time scratching to expose hidden food. Under the backyard and semi-intensive production systems, poultry are usually enclosed at night to discourage thieves and predators, and under intensive production, are totally confined day and night. Some village households keep their few chickens inside the house or even under their bed at night, to discourage theft.

Given a choice of a place to lay their eggs, hens will choose a soft "litter" base, and they prefer an adequately sized (a cube of approximately 30 cm), darkened nest with some privacy. Prior to laying, hens usually investigate a number of possible sites before entering a nest box. They then show nesting behaviour, which includes a special protective nest-seeking voice, after which they sit and finally lay. When they have laid an egg, they announce this with another type of "pride of achievement" call. These calls can also be heard in a battery cage house. If perches are provided, hens will perch most of the time rather than stand on the wire floors, and after dark most birds roost on the perches. Perching is a probable survival characteristic to avoid night predators. The basic requirements for poultry housing are:

• space;

• ventilation;

• light; and

• protection (from weather and predators).

Space: density of birds per unit area

This is the most important basic principle in housing, as the space available determines the number and type of poultry that can be kept. For example, a deep litter house measuring 6 m by 11 m can hold 200 laying hens at a stock density of 3 birds/m² (3.6 ft²/bird). Under the older system of measuring, stock density was measured in ft² per bird, which is the inverse of birds per m² used in the metric system, incorporating a conversion factor of 0.0929 m²/ft² (for details, see the appendix entitled Abbreviations and Conversions).

Linear space or length of perch per bird is measured in centimetres. The recommended floor and perching space for the three main types of chicken is shown in Table 4.1.

Table 4.1 Requirement of chickens for floor and perch space

Chicken types	Floor Space (birds/m2)	Floor Space (ft2/bird)	Perch Space (per bird)
Layer	3	3.6	25 cm (10 in)
Dual Purpose	4	2.7	20 cm (8 in)
Meat	4-5	2.1-2.7	15-20 cm (6-8 in)

Hen groups are comfortable at a stock density of three to four birds per square metre. If more space is allowed, a greater variety of behaviour can be expressed. Less space creates stressed social behaviour, allowing disease vulnerability and cannibalism and leaving weaker birds deprived of feed or perch space. Individual birds need more room for normal behaviour and adequate exercise than the 22 birds/m² (0.5 ft²/bird) density currently used in commercial laying cages. Over recent decades, animal welfare concerns have encouraged research on laying cage structures to make designs better suited to the needs of hens, while retaining cost-effectiveness for production.

Ventilation: air flow

Ventilation is an important factor in housing. A building with open sides is ideal, otherwise cross-ventilation at bird-level should be allowed for in the form of floor level inlets, open in a direction to allow the prevailing wind to blow across the width of the building. An air mass between the side walls of a poultry house resists being moved, even across an open-sided building. The wider the building, the more the resistant it is to air movement. Buildings over 8 m (26 ft) wide have a significantly greater problem because of this inherent property of air to resist movement. It is recommended that buildings relying on natural airflow for ventilation should not exceed 8 m in width.

Heat stress is a significant constraint to successful production and can lead to death. Although birds can withstand several degrees below freezing, they do not tolerate temperatures over 40 °C. This depends on the relative humidity prevailing at the time. Poultry do not possess sweat glands and must cool themselves by panting out water in their breath, which is evaporative cooling. When the humidity is too high, this cooling mechanism does not work very well. Lethal temperatures for most chickens are 46 °C upwards, and severe stress sets in above 40 °C. In temperate regions, the chicken house may be constructed to face the rising morning sun to gain heat. In the tropics however, an east-west orientation of the length of the building helps to minimize exposure to direct sunlight. Building materials such as tin or other metal should be avoided for this reason, although white paint will reflect up to 70 percent of incident solar heat radiation. Ventilation concerns in building alignment may prevail over solar heat control in this aspect, as cross-flow ventilation requires the side of the building to face the prevailing wind.

Ground cover can also reduce reflected heat. Shade should be provided, especially if there is little air movement or if humidity is high. With no shade, or when confined in higher temperatures, poultry become heat stressed and irritable, and may begin to peck at one another. When new pinfeathers are growing (especially on young stock), blood is easily drawn, which can lead to cannibalism. The effects of heat stress are:

• a progressive reduction in feed intake as ambient temperature rises;

• an increase in water consumption in an attempt to lower temperature;

• a progressive reduction in growth rate; and

• disturbances in reproduction (lower egg weight, smaller chicks, reduced sperm concentration and an increased level of abnormal sperm in cocks).

Light: duration and intensity

A well-lit house is essential. A dark house leads to lethargic, inactive, unproductive birds. Light is important for feeding, as poultry identify food by sight. This is especially important for intensively managed day-old chicks, which need very bright 24-hour lighting for their first week of life.

Light is also an important factor in sexual maturity. An increasing light proportion in the day, as naturally occurs from mid-winter to mid-summer, will accelerate sexual maturity in growing pullets, bringing them to lay sooner. If hens are already laying, the increasing light proportion will increase egg production. The opposite effect is also true: as the light proportion of the day decreases (as naturally occurs from mid-summer to mid-winter), then sexual maturity is slowed in growing stock, and egg production is reduced in laying hens. These effects are somewhat reduced towards the equator, as the difference in the daylight proportion of a day changes less and less.

This physiological effect on poultry is important in terms of maintaining egg production in commercial flocks, and requires supplementary lighting programmes. Regular and reliable electricity supply is required for such programmes, otherwise the effect can be made worse by breaks in the light supplementation system. A slow but steady increase maximises the rate of production. However, lighting programmes producing an effective daylight proportion in excess of 17 hours per day can have a worsening effect on egg production. A 24-hour security lighting system can have such an effect on egg production.

Birds do best in situations where there is plenty of natural light that does not raise the temperature of the house. Natural light is preferable unless regular, reliable and well-distributed artificial light can be provided. It is recommended that the interior of the house be whitewashed to reflect light. The intensity or brightness of the light is also important. Egg production will decrease at light intensities lower than five lux (the "lux" is the metric unit of light intensity and can be measured by a meter similar to that measuring light intake into a camera lens), although meat chicken will keep growing optimally at light intensities as low as two lux (not bright enough to read a newspaper). These intensities are measured at the eye-level of the bird, not near the light source. Unless supplementary lighting is spaced uniformly, there may be areas in the building insufficiently lit to allow optimum growth or egg production. Designs for layout assume that the light bulbs or tubes will be kept clean, as dusty surfaces will reduce light output.

Protection: shelter sheds and buildings

Many factors influence the type and choice of housing to protect poultry from the effects of weather and predators. These include the local climate, the available space, the size of the flock and the management system. In extensive systems, birds must be protected from disease and predators but also be able to forage. Traditional large animal fencing using live plants is not enough protection against predators such as snakes, kites, rats and other vermin.

A simple and effective system to deter predator birds is to tie parallel lines of string across the main scavenging area, the intervals between which measure less than the predator's wingspan; or, alternatively, a fishing net supported on poles can be spread across the side of the run where predator birds could swoop on the scavenging chicks.

Leg traps can be set for large predators. It is not necessary to set traps around all the pens, as predators tend to attack the same pen on the second night. Steel traps can be boiled in walnut hulls or cocoa pods, both to camouflage them and to prevent rust. The traps will be more effective if not touched with bare hands, as most predators have a keen sense of smell. Instead, they should be handled with a stick, rubber gloves or tongs.

Rats, mongooses and snakes are only a problem when the birds are small. Rats often come up through the earth floors, and the first signs of a rat attack may be unusually quiet chicks huddled under the brooder heater or in a corner, or dead chicks with small bloody neck scratches. Snakes will kill chicks if they can get into the brooder house. A treble fishhook in a dead bird can be left as bait: the snake will swallow the hooks as it gulps down the bird and eventually die. Holes around doors and windows through which rats and snakes may enter should be plugged.

Coops or baskets may be used to house mother hens and chicks in order to reduce chick mortality due to predators, thieves and rain. They also allow for separate feed and water supplementation, although the inadequate feed usually provided in coops means that some scavenging remains necessary.

Table 4.2 Predator attack modes and control methods

Predator	Attack mode	Control method
Hawk	Picks up stray birds and weaklings. Attacks birds so that head and toe marks are visible on back. Often plucks birds.	Hunt the hawk and keep chicks away from clear swoop areas.
Rat, mongoose	Usually take more than they eat, and stuff chicks in holes for later consumption.	If allowed, use rat poison.
Snake	Will swallow eggs and chicks	Use fishhooks.
Dog, cat	General destruction	Try to catch them. Cats can control rats but wild cats and dogs are a problem.
Fox, jackal	Will bite off the feathers over the back and between wings, eat the entrails and breast, and carry bird to den.	Roam in the early morning; kill for their young. Trapping is the best control.
Raccoon	Pulls off head and eats crop. Will carry birds off.	May be protected in some countries. A permit to destroy may be required.

HOUSING IN FREE-RANGE SYSTEMS

Overnight shelter which is roomy, clean and airy should be provided under free-range systems. Houses may be either fixed or mobile. If space permits, a mobile chicken house may be appropriate, and to increase egg production, mobile folds or field units for laying birds can be provided. These mobile units can be rotated on the range. Although housing is cheaper and there is less need for balanced rations, the birds are exposed to the sun and prone to parasite infestation.

The stocking density on pasture should be calculated according to the soil type and pasture management system. A night shelter for up to 20 free-range chickens can be attached to any existing structure, such as the farmer's outhouse, kitchen or dwelling. In a deep litter system, there should be a density of at most three to four birds per square metre. In regions where it rains heavily, the floor should be raised with a generous roof overhang, particularly over the entrance. The raised floor can be a solid platform of earth or a raised bamboo platform. The raised bamboo platform has the advantage of providing ventilation under the poultry, which helps cool them in hot weather and keeps them out of flood water in the monsoons.

The walls of the building can be made of mud or bamboo, and the windows and door of bamboo slats. The house can also be free-standing, and may also be suitable for semi-intensive or intensive production systems.

HOUSING IN SEMI-INTENSIVE AND INTENSIVE SYSTEMS

Planning

Complete confinement is only advisable where:

• there is good management;

• reproduction is spread equally over the year;

• land is scarce or inaccessible all year round;

• balanced rations are available;

• a supply of hybrid day-old chicks is available;

• labour is expensive;

• parasite and disease control are readily available; and

• the objective is commercial production.

The reasons for confinement are, in order of priority, to:

• reduce mortality due to predation in chicks under two months of age;

• achieve higher daily gain and better feed conversion in growers; and

• allow better supervision of production in laying hens.

In all confined systems, the location and building design must be carefully considered. The area surrounding the house should be mown or grazed. A good location should meet the following criteria:

• It should be easily accessible.

• There should be a reliable water supply.

• The ground should be well drained.

• It should be at a sufficient distance from residential areas (far enough to protect human health and close enough to provide security for the birds).

• It should be well away from woodland.

Converting existing facilities can provide housing, although planning permission may have to be obtained. An unused outhouse kitchen, for example, can be converted into a poultry house. In all conversions, maximum use should be made of the space available through careful planning:

• A plan of the building should be drawn to scale.

• Use should be made of existing floors and walls, if suitable.

• Space requirements of the birds and manure disposal should be taken into consideration.

• A feasibility study should be carried out, taking into consideration future plans and requirements as well as the economics of converting the building.

Construction

The floor is extremely important. An ideal floor for a deep litter house is well drained and made of concrete, with a layer of heavy gravel or wire mesh embedded in it to keep out rats. This type of floor is usually costly. Wood, bamboo, bricks or large flat stones (according to what is locally available) can be used, but are harder to clean. Clay floors are cheaper, but require the application of a fresh layer of clay either between flock batches or at least annually. In areas where construction materials are cheaper than deep litter, and particularly in humid regions where litter material is not available, raised floors are sometimes used. These are made of wire mesh, expanded metal, wooden slats or split bamboo, to allow the droppings to collect under the house, and should be about one metre above the ground to allow for cleaning and ventilation. Higher floors may result in an unstable building. They are supported by pillars, which are either rot-resistant or have stone or concrete footings, and which are made of such materials as wood, bamboo, oil drums and concrete blocks. Houses with raised floors on posts can be protected against rats with baffles. The baffles can be made of a metal collar, a tin can turned upside-down or a metal band wound around the post, but must fit tightly to deter even the smallest rodent.

The roof and walls of the house can be made of any inexpensive local material, including bamboo slats, sorghum stalks, mud, wooden slats and palm fronds, as long as the structure is made relatively rat-proof. In colder regions, the walls should be thicker or insulated, but in warmer climates thatch can be used, although it should be replaced frequently to minimize parasite and disease problems. The inside of the walls should be as smooth as possible, to prevent tick and mite infestation and to make cleaning easier. Interior length-ways building partitions are not advisable, as they reduce cross-flow ventilation.

The roof should be watertight, and should overhang the walls by one metre if the windows have no shutters. The roof can be made of thatch, sheet metal or tiles. Thatch is usually the cheapest option and provides good insulation. It will probably have to be replaced every three years, or immediately if ticks get into it. It should be interlaced with bamboo or wooden slats to keep predators out. Sheet metal is usually too expensive, and in hot climates must be painted with white or aluminium to reflect sun heat. However, it is easily cleaned which is an important advantage where ticks are a problem. A layer of plastic sheeting sandwiched between bamboo slats is a good seal against rain and vermin. Flattened oil drums can be used at a lower cost. Although usually more expensive than thatch, sun- or oven-baked tiles will last much longer. Because of their weight, the frame for a tiled roof must be stronger than for other materials.

Window design depends on the local climate. Chickens need more ventilation than humans, but should be sheltered from wind, dust and rain. During storms, wood or bamboo hinged shutters or curtains made from feed sacks can cover window openings on the windward side of the house. In humid climates, window design should take as much advantage of the wind direction as possible to reduce the amount of moisture in the house. Window areas are best covered by wire mesh or expanded metal. Wooden slats or bamboo can be used, depending on available funds and materials. However, the thicker the material, the more ventilation will be reduced. Doors should be made of metal, wood or bamboo. The top half of the door could be wire mesh. Doors should be sufficiently strong to withstand being opened and closed many times a year.

Gabled roofs reduce solar heat loading when compared with flat or lean-to roofs. The pitch or "angle of rise" on a gabled roof is important for many reasons. Traditional village thatched gabled roofs are usually constructed using bush timber, and at a steeply pitched angle (greater than 42° from the horizontal), which helps the roof to withstand stormy winds. Shallower pitched roofs are more susceptible to being blown off in strong winds, particularly when the pitch angle is 15° to 20°. Shallower pitched roofs have less roof surface area, which reduces the cost of surfacing material, but because they are more affected by stormy winds, they need stronger support frames, which results in a much higher overall roof cost. A 42° pitch is the optimum compromise between roof surfacing costs and roof support costs.

The maximum width for an open-sided poultry building, under conditions of a slight breeze, which allows air movement across the shed at the height of the bird, is 8 m (26 ft). To maximise the volume and velocity of airflow across the shed width, the end walls of the shed should be closed. This forces the air to flow across the shed width, especially if the wind is not already coming from that side. Centre ridge ventilation is not recommended, as it discourages airflow across the full shed width. Air enters at the prevailing wind side and is drawn up at the centre to exit at the ridge, excluding the other half of the building.

Nests

To avoid excessive competition and minimize eggs laid on the floor, one nest should be provided for every five hens. If larger communal nests are used, at least one square metre per 50 birds should be allowed. Baskets, pots and cardboard boxes can be used for nests. Dimensions suitable for a basket or pot nest are a 25 cm base diameter, 18 cm high walls, and a 40 cm open top diameter. Nests should be situated in a secure, shady secluded place out of the sun, lined with fresh litter and kept clean. Nest boxes for individual hens should be constructed in multiple groups for larger numbers of hens. These are usually made of wood, and should measure approximately 30 cm on all sides, with a nest floor area of about 0.1 m^2.

Perches and roosts

Chickens prefer to roost at night on perches. Perching space of 15 to 20 cm should be allowed for each bird. Birds lower in the social peck order can also use the perches during the day. The cross-section of each perch bar should be 2 to 3 cm. Their length depends upon the number of birds to be housed. The perches should be placed within a frame, and aligned parallel to the wall, and horizontally, with a sliding, removable platform called the "droppings board" about 20 cm below the perches to catch the manure droppings. The first perch bar should be placed 20 to 25 cm out from the back wall, and subsequent ones at 30 to 40 cm intervals. The droppings board should touch the back wall and extend 30 cm in front of the front perch bar, as this will allow the birds to land from their flight from the floor before seeking a perching spot. Droppings boards should be a maximum of 75 cm from the floor of the house, and the perch bars should be about 20 cm above the droppings board, to facilitate cleaning of the droppings board. Fowls deposit over half their droppings at night, and the use of the droppings boards thus helps to keep the floor clean. The manure can then be easily collected, dried and stored in empty feed sacks for use as an excellent fertilizer for plants requiring organic nitrogen. The area under the droppings board then becomes an ideal site for a communal nest.

Providing feed

In both intensive and semi-intensive systems, laying hens need constant access to food and water, and feeders should be distributed evenly throughout the chicken house. In the semi-intensive system, birds scavenge during the day, mostly for protein (from such sources as insects, worms and larva), minerals (from stones, grits and shells), and vitamins (from leafy greens, oil palm and nuts), but energy supplements such as maize, sorghum and millet are important for higher productivity and should be given. Chapter 3 on Feed Resources discusses ingredients and feeding systems in more detail.

Feeders

A good feeder should be:

• durable enough to withstand frequent cleaning;

• stable enough not to be knocked over;

• of the correct height and depth;

• bird proof (such that birds cannot get into it or roost in it); and

• equipped with a lip to prevent birds from spooning feed out onto the floor with their beaks.

The height of the feed inside the feeder, which should never be more than one-third full, should be level with the back of the birds, to prevent them from scratching contaminated litter into the feeders and to limit feed wastage. This is achieved by adjusting the height of the feeder itself. To reduce spoilage and mould problems, feed should be supplied at sunrise and at about 14.00 hours (or more frequently if the birds empty the feeder), with all feed finished by sundown. Feeders can be made of wood, sheet metal or bamboo, and are best suspended from the roof to keep rats out. The height of the feeder should be adjustable. Supplementary vegetable matter should be fed at beak level, either hanging from the ceiling wrapped in a string or placed in a net or placed in a floor-standing hopper with wire or slatted sides. It should not be thrown on the floor.

Feeder space is measured as the linear distance of lip available to the birds. This is either the circumference of a round tube-feeder tray or twice the length of a trough if the birds feed from both sides. If troughs are used, at least 10 cm of feeding space should be accessible to each bird. When circular feeders are used, there should be at least 4 cm feeding space per bird.

Table 4.3 Feed and feeder space requirements for 100 chickens

Age (weeks)	Daily feed consumption (kg)	Suggested feeder depth (cm)	Feeder space (m)
1 - 4	1.4 - 5.0	5	2.5
4 - 6	3.2 - 7.3	8	3.8
6 - 9	5.0 - 9.5	9	6.1
10 - 14	7.3 - 15.9	12.5	9.6
15 and above	9.1 - 11.4	15	12.7

Creep Feeders

Creep feeders are used to enable baby chicks to have access (by "creeping" through a small doorway) to high-quality (high in energy and protein) feed, while blocking access to larger sized birds (especially the chicks' mothers). The conical (open at the top and base) creep feeder can be made from split bamboo strips approximately 0.5 to 1 cm wide, bound at the joints with string or wire. The base of the creep feeder can be 75 cm in diameter and 70 cm high, with an access hole (reinforced to form a carrying handle as well) about 20 cm wide at the top. The gaps between the upright slats can be 2 to 3 cm at the bottom and about 1 cm at the top. The flexibility of the bamboo strips allows the size of the entryways to be enlarged, as the chicks grow bigger. If the chicks are reluctant to leave their mothers' side, then a more tightly formed weave can prevent their exit once they are placed inside the cone through an opening at the top. The bamboo can be preserved from insect attack with a coat of used engine oil.

Better nutrition for young stock boosts their immune response to disease challenge and to vaccine response by developing full immunity. Gunaratne et al (1994) reported that chick mortality rates could be reduced by the use of creep feeders but that this did not increase the growth rate. However, when the household waste was supplemented with protein and fed in the creep feeder, both the growth and the survival rate of chicks increased (Roberts et al., 1994).

Table 4.4 shows that annual egg production can be doubled because of the increased laying time available to the hens if their chicks are fed in a creep feeder after hatching (Pratseyo et al., 1985). If the gaps in the creep feeder are adjusted, it can also be used for growers over eight weeks, and if given less than the full ration, they will learn to compete for food with other chickens.

Table 4.4 The effect of creep feeding on flock egg production

Intervention	Period
	June	July	Aug.	Sept.	Oct.	Nov.
Creep only	31.5	28.7	27.3	21.8	21.4	33.0
Creep + Low supplement	21.2	18.8	22.9	26.9	30.7	31.1
Creep + High supplement	24.3	24.5	32.5	34.1	27.4	31.1

Source: Gunaratne et al., 1993

Providing water

Providing clean water is a priority often neglected. The amount of water, the right type of equipment and where it is situated are important considerations. Table 4.5 shows water consumption rates for hot dry conditions, and these can be halved for temperate regions.

Table 4.5 Minimum water and watering space requirements for 100 birds in hot dry conditions

Age (weeks)	Daily consumption (litres)	Water space (m)
0 - 1	3	0.7
2 - 4	10	1.0
4 - 9	20	1.5
9 or more	25	2.0
Layer	50	2.5

In countries with plenty of water, such as Bangladesh, Viet Nam, Indonesia, the Gambia, Sierra Leone, Zaire and Uganda, the only special measure to be taken is to ensure its cleanliness. In other regions, especially in the Sahel and other drought-prone regions, fetching and carrying water is a crucial task, usually assigned to women and children. In the rainy season, clean water and feed must be placed in the house, as brooding hens are kept inside to prevent poor hatchability resulting from contamination with mud and dirt.

The simplest equipment is a tin can inverted into a soup plate or the bottom of a larger tin can. A hole is punched about 2 cm from the open end of the tin can. The can is filled with water, covered with the plate and both quickly inverted. The position of the punched hole and the vacuum in the tin can will regulate the water level in the plate. Tin can waterers work well but quickly become rusty, especially in the humid tropics. A clay pot or gourd with holes around the sides sunk into the ground for stability can be used to water adult birds. Clay pots of any dimension can often be ordered from local pot makers. Because they are permeable they provide water half a degree Celsius cooler than other waterers, as heat loss through evaporation keeps the water cooler. This also means an appreciable loss of water over time, especially in very hot dry areas, so that the pots may have to be made more impermeable by glazing. If continuous drinking troughs are used, at least 5 cm of trough should be allowed for each bird. Alternatively, one cup or nipple drinker may be provided for every ten birds.

BABY CHICK MANAGEMENT

Baby chicks should be kept warm and dry. The nest, which they share at night with the mother hen, must be kept clean. In colder climates (below 20 °C at night), the nest site should be kept warm by lining it with straw and placing it near a stove or fireplace. The chicks should remain with the mother hen for nine to ten weeks, learning from her example how to scavenge and evade predators and other dangers. Clean drinking water and fresh feed in a clean container should be provided to supplement scavenging. See Chapter 3 "Feed Resources" for more detail on feeding techniques.

There is a close relationship between chick weight and growth and mortality rates. In an experiment where young chickens had access to supplementary feed in a creep feeder (Roberts et al., 1994), it was found that supplementary protein feed had a significant effect on the survival rate and growth rate. Chicks separated from the mother hens during the day from the age of three to ten weeks, and fed with chicken starter mash ad libitum, had a mortality rate of 20 percent and a body weight of 319 g at ten weeks, compared with a mortality rate of 30 percent and a body weight of 242 g for the control group which remained with the mother hens. See more supplementary detail in the section above, entitled "Creep Feeding". A suitable strategy for rearing chicks therefore would be as follows:

• The chicks should be confined for the first weeks of life and provided with a balanced feed.

• A vaccination programme should be followed.

• Sufficient supplementary feed should be provided during the remaining rearing period to allow the chickens to develop in accordance with their genetic potential.

• Feed supplements and protection should be provided to naturally brooded chickens during the first four to eight weeks of life.

The composition of the supplementary feed will depend on the available scavengable feed, but a form of cafeteria free-choice feeding of a protein concentrate, energy concentrate and calcium mineral in each of three containers may be the best solution.

The mortality rate of naturally brooded chicks, whose only source of feed is from scavenging under free-range conditions, is very high and often exceeds 50 percent up to eight weeks of age. Wickramenratne et al (1994) found that predators accounted for up to 88 percent of mortality and that coloured birds had a higher survival rate than white birds. The high mortality rate and the large number of eggs required for hatching are the main causes of low offtake from scavenging poultry flocks. Smith (1990) reported an offtake (sales and consumption) of only 0.3 chickens per hen/year from a survey done on flocks in Nigeria. This low offtake has also been observed in Bangladesh and India.

An efficient way of decreasing mortality rate (a costly loss) is to confine and vaccinate the chicks during the rearing period. This however is more expensive, the cost of feed in particular increasing production costs. A method used over the past ten years in many poultry development projects in Bangladesh confines the chicks during the first eight weeks of life. They are fed approximately 2 kg each of balanced feed and thereafter kept under semi-scavenging conditions. At eight weeks of age, they are less susceptible to attacks by predators and more resistant to diseases, due to their larger body weight and more effective vaccination immunization (due to their better nutrient intake).

HYGIENE

Manure management

Whatever the type of confinement, proper attention must be paid to manure management. Adult birds produce 500 g of fresh manure (70 percent moisture content) per year per kg of body weight. To preserve its fertilizer value, manure should be dried to about 10 to 12 percent moisture content before storage. This will retain the maximum nitrogen content for fertilizer value. Nitrogen in the form of urea is the most volatile component of manure, and is lost as ammonia if moisture content is too high in the stored material. If the moisture content is too high, then the stored manure releases ammonia, carbon dioxide, hydrogen sulphide and methane, which can have serious physiological effects on humans. Some of these components are also greenhouse gases, which contribute to the global increase in ambient temperature. Poultry manure is very useful as an organic fertilizer, as animal and fish feed and as a raw material for methane gas generation in biogas plants for cooking fuel.

Other hygiene management measures

Good ventilation discourages the spread of diseases and pests. In overnight houses, the provision of perches or loosely plaited bamboo mats (such as those used for sieving) placed on the floor can help to keep them dry.

If the birds are housed inside, the floor should be swept daily. An outside chicken house should be cleaned every week to break the breeding cycle of the common housefly. It takes about seven days to complete the breeding cycle from fly egg to hatching of the adult housefly. Wood ash and sand spread on the floor will discourage lice infestation. Mothballs (naphthalene) crushed with ash can also be applied to the feathers or the wings of the birds, or placed where the chickens usually take their dust baths. If the chickens are already infested with mites, the house can be fumigated (while the chickens are outside) with a rag drenched in kerosene. Lice live on the birds, and dust baths with naphthalene powder in the ash will be more effective than dust alone.

The practice of keeping chickens and ducks together should be discouraged. This results in wet floors, giving rise to diseases such as Fowl Cholera. Ducks are also much more tolerant than chickens to Newcastle Disease, and are thus often carriers of this viral disease. Adults and young stock of any poultry should be housed separately to minimize cross-infections and injuries from bullying.

MANAGEMENT OF FREE-RANGE POULTRY

The unrestricted free-ranging of poultry is often a problem. They trespass onto neighbouring fields and gardens, and are constantly at risk from predators. Confinement is often not practical because of the cost of feed and fencing, while surveillance is only feasible where the very old or very young of the household have time to help. Fencing of vegetable plots is in many cases the best option. Placing more cocks in the village might reduce the movements of the chickens, as the cocks and hens of each flock would keep more to their own territory. Cocks move within an eight-to-ten-house territory, and hens within two or three houses.

Under the free-range system, the difference between the amounts of food gathered through scavenging and the total food requirement for maximum production should be balanced with nutrients supplied from supplementary feed. To make up a properly balanced supplement, it is necessary to know the scavenger feed resource base (SFRB) and the composition of the crop contents (see Chapter 3, SFRB). If this is not known, it is recommended that the fowls have access (using a free-choice cafeteria system) to three containers (or three compartments of a bamboo stem feeder of ingredients comprising a protein concentrate, a carbohydrate source (for energy) and a mineral source (mainly for calcium carbonate for egg shell formation for the hen). Poultry should have free access to this cafeteria system for two to three hours in the evening to supplement the day's scavenging.

From a feed resource point of view, this recommendation is only economically viable (sustainable) if the consumption of supplementary feed per egg produced is equal to 150 to 180 g or less. Consumption of over 150 g is only justified if the supplements are cheaper than the commercial feed used in intensive poultry production. Supplements are usually recommended in the range of 50 to 80 g/bird/day, so it is usually quite viable. Seasonal variations in the SFRB have a substantial effect on production. During the dry season, scavenged feed from gardens, crops and wasteland (such as grass shoots, seeds, worms, insects and snails) stops, while the quantity and quality of household kitchen waste decrease. The feed supplement should be adjusted seasonally to maintain an optimum level of production or, alternatively, the chicken population could be adjusted to the amount of the SFRB and the feed supplement.

Hens in confinement fed a balanced diet will convert food weight to egg weight at an efficiency of about 2.8 kg of feed per kilogram of egg weight. Changes in husbandry alone may increase the productivity of scavenging village chickens, without the need for additional inputs. In planted orchards, a stocking rate of 120 to 180 birds/ha will clean up windfalls while also fertilizing the trees. In this example, the amount of fertilizer produced per hectare for 150 hens (weighing two kilograms each) is based on the assumption of 500 g of fresh (70 percent moisture) weight of manure produced per kilogram of live weight per year. This results in 330 g of dried manure (dried to a ten percent moisture content) per hen/year, and thus the 150 hens will produce 49.5 kg of dry manure per year. This has an equivalent fertiliser value of 13 percent ammonium nitrate, 8.6 percent super-phosphate and 2.9 percent potash (potassium) salts. Thus the 150 hens will produce the equivalent per hectare/year of 6.4 kg of ammonium nitrate, 4.3 kg of super-phosphate and 1.4 kg of potash salts.

Planning flock production and size

Production involves birds for meat and eggs. For both meat and egg production, the number of chickens in the flock is the most important factor. Flock size changes constantly as eggs hatch and hens are sold or eaten. Usually the main cause of flock depletion is mortality, particularly in chicks. Disease is the greatest cause of mortality, especially in the rainy season and in the weather changeable humid periods on either side. During summer and the rainy season, predators in the cropped fields also contribute to reduced flock sizes. Local birds lay an average of three to four clutches of 12 to 15 eggs in a year, with more eggs laid at crop harvest time because more feed is available. Given most traditional farming systems, keeping the flock number constant requires eight to ten eggs for reproduction, leaving an average of 35 to 40 eggs per layer for sale or consumption. Because the number of eggs needed for replacement may decrease with better management, the extra eggs can be sold or eaten.

Most egg laying takes place between sunrise to mid-morning. During the months of laying, nest location should not be moved, as this may upset the laying routine.

In village flocks, income derives from the sale of eggs and live birds. For example, a flock of 15 local hens laying 30 eggs/hen/year (with one local cock) will produce 450 eggs in a year. Of these 450 eggs, 120 may be incubated by broody hens (in ten clutches of 12 eggs each), of which 100 chicks may hatch, and 30 eggs may be cracked and consumed in the household, leaving a balance of 300 eggs for sale. Of the 100 day-old chicks, 30 may reach maturity (with rearing losses of 70 percent), to yield 15 cockerels and 15 pullets. The 15 pullets will replace the older hens, of which ten remain after the sale of cull hens, and one new cockerel will replace the old cock. The annual income from the flock can therefore be calculated as follows:

300 eggs + 10 old hens + 1 old cock + 14 cockerels = income

For improved productivity, culling is important and productive birds should be carefully selected. For simplicity, the above example assumes no adult mortality.

CASE STUDIES OF FAMILY POULTRY MANAGEMENT SYSTEMS

A free-range system in Ghana

In the traditional free-range system of the Mamprusi tribe in northern Ghana (van Veluw, 1987), the farmer releases his 19 chickens and six guinea fowls from the space under the grain store each morning. Grains are thrown on the ground to feed the birds. A young boy takes care of the birds during the day and protects the crops from poultry damage. Occasionally the boy will feed the birds with a piece of termite hill, and in the evening he returns with the flock and locks them under the granary store.

Chicken hens lay throughout the year, but guinea fowls lay only in the rainy season. Chicken hens produce about 20 to 40 eggs a year and guinea fowls about 50. Most of the eggs are used for hatching. Chickens also hatch guinea fowl eggs, as guinea fowls are not good mothers. Hatching takes place throughout the year, although most of the hens incubate their eggs in the rainy season. A reproduction cycle (laying, hatching, caring for chicks and resting) takes about 20 weeks. Mortality is high (75 percent) among the young chicks. Out of ten chicks, only about two reach adulthood, due mainly to disease, predators and road accidents. Newcastle Disease in particular kills many poultry in the dry season. Worms as internal parasites are a great problem, weakening the birds. Predators include snakes, birds of prey, cats and dogs. Mortality up to two months of age is 50 percent, with a further 25 percent thereafter up to sexual maturity.

Hatchability of guinea fowl eggs is very low (45 percent) compared with chickens (72 percent). Farmers keep hens for about three years and guinea fowls for two years, after which productivity decreases considerably and they are culled.

Table 4.6 Total annual production of a Mamprusi average flock

	Chickens		Guinea fowls		Total Production
	Flock	Production	Flock	Production
Cocks	3	1	2	1	2
Hens	9	3	4	2	5
Cockerels	2	22	-	13	35
Pullets	5	19	-	11	30
Eggs (/hen)	-	45 (20)	-	65 (50)	110 (380)

Scavenging commercial hybrid layers in Sri Lanka

In a study carried out by Roberts and Senaratne (1992), Sri Lankan villagers reared hybrid egg layers in a semi-scavenging system. Day-old hybrid chicks were brooded under the heat of a small kerosene lamp. The chicks were provided with a little mixed supplement of local crop by-products, comprising 40 percent rice polish, 50 percent expeller coconut meal and 10 percent broken rice. The Proximate chemical analysis of this supplement was 16 percent Crude Protein, 8 percent Crude Fat, 7 percent Crude Fibre and 7 percent Ash.

The amount of the supplement increased from 8 to 60 g/bird/day until 12 weeks of age, and was maintained at 60 g thereafter. The growth rate was 38 g/bird/day up to 20 weeks of age. The mortality rate of the chicks was only four percent in the period up to ten weeks, which compared favourably with mortality of 68 percent up to six weeks in Indonesia (Kingston and Creswell, 1982) and 25 percent up to eight weeks in Thailand (Thitisak et al, 1989) in chicks hatched and reared by village hens. The comparative advantage of the Sri Lankan performance was attributed to supplementing the competitive scavenging, and to the protection against predators provided by the semi-intensive management system. It is probable that chicks would also benefit from the use of a simple creep feeder for feeding kitchen waste. The mortality rate, in the Sri Lankan example, increased after reaching eight months of age, perhaps due to a greater need for scavenger free-ranging, and almost reached a cumulated 60 percent loss by 13 months of age. Of the 142 hens lost up to 13 months of age, records were kept for 92. The causes of mortality were:

• 32 percent predators (such as dogs, mongooses, pole cats and snakes);

• 26 percent disappeared;

• 15 percent Newcastle disease;

• 15 percent intestinal infection;

• 5 percent stolen;

• 4 percent accidents (vehicles and falling coconuts); and

• 2 percent attacked by humans.

Hens laid their first eggs when they reached 21 weeks (146 days) of age, although 40 percent production (on a hen/day basis) was not achieved until they were 30 weeks of age. Peak egg production was just over 60 percent. A severe drop in production (beginning when the hens were eight months of age) corresponded with an outbreak of Newcastle Disease in local village birds and the start of the long dry intermonsoon period. Production fell to below 30 percent when the hens were ten months of age, and slowly rose again to over 60 percent at 13 months of age. The recovery in production began during the dry period and was maintained into the next season. Egg production was comparable with that of hybrid egg layers, which were introduced into the village as pullets, provided with a supplement and allowed to scavenge.

The production was much better than the 12 to 21 percent reported in village birds in Indonesia (Kingston and Creswell, 1982) and in Thailand (Janviriyasopaki et al, 1989) and (Creswell and Gunawane, 1982). The egg weight reported by Roberts and Senaratne (1992) was 60 g compared with about 40 g for village hens (Kingston and Creswell, 1982).

A free-range system in Senegal

In a study carried out on farms in Senegal (Sall, 1990), flock sizes ranged from under five birds to more than 15 birds, with an average flock size of ten birds. Seven percent of the flocks comprised under five birds, 38 percent comprised five to ten birds, 41 percent comprised 10 to 15 birds, and 14 percent comprised more than 15 birds.

Flocks with fewer than five birds had either recently lost hens or had hens that had not yet hatched their eggs. Flock size varied considerably during the year, due to additions (hatchings, purchases and gifts) and to chickens either sold or lost through disease or predators. The birds were permitted to scavenge during the day and were locked into wooden cages (ngounou) at night for protection. The cages were made on the farm from available materials (including bricks, galvanised iron sheets and wood). The doors were small, to prevent entry by thieves and predators. Stock density in the cages was about 25 birds/m². Feed and water was available to supplement kitchen waste and scavenging.

The proportion of young chicks and growers in the flock was about 60 percent while adults represented 40 percent. Mortality in the first month of age was 40 percent. There were four to five clutches of eggs laid per year, with 8 to 15 eggs per clutch. Egg weights ranged between 38 and 43 g with an average of 40 g. Almost all eggs were set for hatching and of these hatchability was about 80 percent. The production cycle was eight to ten weeks (10 to 15 days for egg laying, 21 days for incubation, and only 34 days for rearing). The chicks remained close to the hens for up to two weeks, during which time there was a relatively low mortality rate of 14 percent. On leaving the immediate protection of the hens, mortality increased sharply to 40 percent between three and four weeks, and up to 66 percent by three months of age. Similarly, the average daily live-weight gain of birds under this extensive system decreased from 10 g at eight weeks to 6 g at 12 weeks.

Table 4.7 Village flock structure in Senegal Source (Sall, 1990)

Age (months)	N°	Males	N°	Females	N°	Total %
0 - 1	-	-	-	-	320	50.5
1 - 3	-	-	-	-	99	15.6
3 - 6	34	5.4	84	13.3	118	18.6
6 - 8	2	0.3	21	3.3	23	3.6
8 -10	1	0.2	19	2.9	20	3.2
10 +	15	2.4	39	6.2	54	8.5
Total	52	8.3	163	25.6	634	100

Table 4.8 Age-related mortality in local birds in Senegal

Age (weeks)	% Mortality (cumulative)
1	13 ± 5
2	15 ± 9
3	39 ± 20
4	42 ± 20
8	49 ± 20
12	66 ± 17

Source: Sall, 1990, p 37

Table 4.9 Body weight of local birds in Senegal

Age	N°	Males	N°	Females	N°	Males + Females
1 week	-	-	-	-	81	34±5
2 weeks	-	-	-	-	75	58±10
3 weeks	-	-	-	-	66	101±43
1 month	-	-	-	-	98	171±70
2 months	-	-	-	-	41	464±242
3 months	-	-	-	-	58	631±211
4 months	29	975±20	63	746±170	92	860
6 months	5	1380±150	21	1229±165	26	1305
8 months	2	1826±75	21	1264±183	23	1544
10 months	1	1500	19	1245±150	20	1372
+ 1 year	15	1803±4	39	1350±223	54	1577

Source: Sall, 1990

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